Effects of crowdedness on planetary systems containing planets on wide orbits
We consider the effects of high stellar number densities on planetary systems containing planets on relatively wide orbits. In crowded places such as young stellar clusters, a large fraction of stars will experience close encounters with passing stars, or exchange into binaries. Fly-bys can induce instabilities within planetary systems, whilst companion stars can change the eccentricity of planetary orbits via the Kozai mechanism. Planets on wider orbits will generally be more vulnerable to such effects. Here we consider the survival chances of wide planetary systems as a function of stellar cluster properties (mass and radius of cluster).